Occlusion clip

ABSTRACT

A method of using an occlusion clamp, the method comprising: (a) repositioning a tongs so that tissue interposes the tongs, the tongs comprising a first longitudinal segment operatively coupled proximally to a second longitudinal segment, the tongs including a first spring exerting a proximal bias tending to direct a proximal portion of each of the first and second longitudinal segments toward one another, where each of the first and second longitudinal segments includes a distal free end; (b) repositioning a second spring distally along each of the first and second longitudinal segments to exert a bias tending to direct a distal portion of each of the first and second longitudinal segments toward one another, where repositioning of the tongs so that tissue interposes the tongs precedes repositioning the second spring distally along each of the first and second longitudinal segments.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application is a continuation of U.S. patent applicationSer. No. 17/131,975, filed Dec. 23, 2020 and titled, “OCCLUSION CLIP,”which is a continuation of U.S. patent application Ser. No. 15/904,541,filed Feb. 26, 2018 and titled, “OCCLUSION CLIP,” now U.S. Pat. No.10,898,204, which is a continuation of U.S. patent application Ser. No.14/085,836, filed Nov. 21, 2013 and titled, “OCCLUSION CLIP,” now U.S.Pat. No. 9,901,351, which claims the benefit of U.S. Provisional PatentApplication Ser. No. 61/729,023, filed Nov. 21, 2012 and titled,“OCCLUSION CLIP,” the disclosure of each of which is hereby incorporatedby reference.

RELATED ART Field of the Invention

The present disclosure is directed to devices used to occlude anatomicalstructures and, more specifically, to clips that may be used to occludeanatomical structures.

Brief Discussion of Related Art

Embolic stroke is the nation's third leading killer for adults, and is amajor cause of disability. There are over 700,000 strokes per year inthe United States alone. Of these, roughly 100,000 are hemorrhagic, and600,000 are ischemic (either due to vessel narrowing or to embolism).The most common cause of embolic stroke emanating from the heart isthrombus formation due to atrial fibrillation. Approximately 80,000strokes per year are attributable to atrial fibrillation. Atrialfibrillation is an arrhythmia of the heart that results in a rapid andchaotic heartbeat that produces lower cardiac output and irregular andturbulent blood flow in the vascular system. There are over five millionpeople worldwide with atrial fibrillation, with about four hundredthousand new cases reported each year. A patient with atrialfibrillation typically has a decreased quality of life due, in part, tothe fear of a stroke, and the pharmaceutical regimen commonly used toreduce that risk.

For patients who develop atrial thrombus from atrial fibrillation, theclot normally occurs in the left atrial appendage (LAA) of the heart.The LAA is a cavity that looks like a small pocket or windsock that isconnected to the lateral wall of the left atrium between the mitralvalve and the root of the left pulmonary vein. The LAA normallycontracts with the rest of the left atrium during a normal heart cycle,thus keeping blood from becoming stagnant therein, but often fails tocontract with any vigor in patients experiencing atrial fibrillation dueto the discoordinate electrical signals associated with atrialfibrillation. As a result, thrombus formation is predisposed to form inthe stagnant blood within the LAA.

Blackshear and Odell reported that of 1288 patients with non-rheumaticatrial fibrillation involved in their study, 221 (17%) had thrombusdetected in the left atrium. Blackshear J L, Odell J A., AppendageObliteration to Reduce Stroke in Cardiac Surgical Patients With AtrialFibrillation. Ann Thorac. Surg., 1996.61(2):755-9. Of the patients withatrial thrombus, 201 (91%) had the atrial thrombus located within theleft atrial appendage. The foregoing suggests that the elimination orcontainment of thrombus formed within the LAA of patients with atrialfibrillation would significantly reduce the incidence of stroke.

Pharmacological therapies for stroke prevention, such as oral orsystemic administration of warfarin, may be inadequate due to seriousside effects of the medications and lack of patient compliance in takingthe medication.

One approach to LAA exclusion is occlusion of the LAA using a permanentclip. Prior art clips have not been permanently attached to the base ofthe LAA and operate to close off the interior pocket from the atrium.Over time, scar tissue seals the LAA at the point where the tissue issandwiched between the clip, while scar tissue attempts to grow aroundthe clip to maintain it in position. Prior art clips have been closedended so that application of the clip to the LAA is more complicatedbecause it requires feeding the LAA in between opposed spring arms,while concurrently feeding the LAA in between biased straight bars.

Despite the various efforts in the prior art, there remains a need for aminimally invasive methods and associated devices for occlusion of theLAA that allow the clip to be placed from the side of the LAA withouthaving to feed the LAA in between a completely bounded perimeter.

INTRODUCTION TO THE INVENTION

It is a first aspect of the present invention to provide an occlusionclamp comprising: (a) an occlusion tongs including a primary springcoupling a first longitudinal arm to a second longitudinal arm, thefirst longitudinal arm including a first linear occlusion surfaceconfigured to be parallel to and overlap a second linear occlusionsurface of the second longitudinal arm, each of the first and secondlongitudinal arms having a free distal end, and (b) a secondary springremovably coupled to the occlusion tongs.

In a more detailed embodiment of the first aspect, the firstlongitudinal arm, the spring, and the second longitudinal arm areintegrated. In yet another more detailed embodiment, the firstlongitudinal arm includes a first trench extending longitudinally alonga majority of a length of the first longitudinal arm, the secondlongitudinal arm includes a second trench extending longitudinally alonga majority of a length of the second longitudinal arm, at least a firstportion of the secondary spring is configured engage the first trench toremovably couple the secondary spring to the occlusion tongs, and atleast a second portion of the secondary spring is configured to engagethe second trench to removably couple the secondary spring to theocclusion tongs. In a further detailed embodiment, the first trenchincludes a first plurality of cavities and each configured topotentially receive the first portion of the secondary spring tomaintain a relative position of the secondary spring with respect to thefirst longitudinal arm. In still a further detailed embodiment, thesecond trench includes a second plurality of cavities and eachconfigured to potentially receive the second portion of the secondaryspring to maintain a relative position of the secondary spring withrespect to the second longitudinal arm. In a more detailed embodiment,the first plurality of cavities is spaced apart from one another. In amore detailed embodiment, the first plurality of cavities is spacedapart from one another and the second plurality of cavities is spacedapart from one another. In another more detailed embodiment, the firstlongitudinal arm includes a first projection extending longitudinallyalong a majority of a length of the first longitudinal arm, the secondlongitudinal arm includes a second projection extending longitudinallyalong a majority of a length of the second longitudinal arm, at least afirst portion of the secondary spring is configured to engage the firstprojection to removably couple the secondary spring to the occlusiontongs, and at least a second portion of the secondary spring isconfigured to engage the second projection to removably couple thesecondary spring to the occlusion tongs. In yet another more detailedembodiment, the first projection comprises a first plurality ofprojections and each configured to potentially engage the first portionof the secondary spring to maintain a relative position of the secondaryspring with respect to the first longitudinal arm. In still another moredetailed embodiment, the second projection comprises a second pluralityof projections and each configured to potentially engage the secondportion of the secondary spring to maintain a relative position of thesecondary spring with respect to the second longitudinal arm.

In yet another more detailed embodiment of the first aspect, the firstplurality of projections is spaced apart from one another. In yetanother more detailed embodiment, the first plurality of projections isspaced apart from one another and the second plurality of projections isspaced apart from one another. In a further detailed embodiment, thefirst longitudinal arm includes at least one of a first cavity and afirst projection extending longitudinally along a majority of a lengthof the first longitudinal arm, the second longitudinal arm includes atleast one of a second cavity and a second projection extendinglongitudinally along a majority of a length of the second longitudinalarm, at least a first portion of the secondary spring is configured toengage at least one of the first cavity and the first projection toremovably couple the secondary spring to the occlusion tongs, and atleast a second portion of the secondary spring is configured to engageat least one of the second cavity and the second projection to removablycouple the secondary spring to the occlusion tongs. In still a furtherdetailed embodiment, the first projection comprises a first plurality ofprojections and each configured to potentially engage the first portionof the secondary spring to maintain a relative position of the secondaryspring with respect to the first longitudinal arm, and the secondprojection comprises a second plurality of projections and eachconfigured to potentially engage the second portion of the secondaryspring to maintain a relative position of the secondary spring withrespect to the second longitudinal arm. In a more detailed embodiment,the first plurality of projections is spaced apart from one another, andthe second plurality of projections is spaced apart from one another. Ina more detailed embodiment, the first cavity comprises a first pluralityof cavities and each configured to potentially engage the first portionof the secondary spring to maintain a relative position of the secondaryspring with respect to the first longitudinal arm, and the second cavitycomprises a second plurality of cavities and each configured topotentially engage the second portion of the secondary spring tomaintain a relative position of the secondary spring with respect to thesecond longitudinal arm. In another more detailed embodiment, the firstplurality of cavities is spaced apart from one another, and the secondplurality of cavities is spaced apart from one another. In yet anothermore detailed embodiment, the spring comprises a discontinuous ringhaving a first end and a second end, the first end is spaced apart fromthe second end, the first end is mounted to the first longitudinal arm,and the second end is mounted to the second longitudinal arm. In stillanother more detailed embodiment, the first end includes a first planarsurface, the second end includes a second planar surface, and the firstplanar surface extends parallel to the second planar surface.

In a more detailed embodiment of the first aspect, the firstlongitudinal arm includes a first arcuate boundary defining a firstarcuate depression, the second longitudinal arm includes a secondarcuate boundary defining a second arcuate depression, and the primaryspring interposes the first arcuate boundary and the second arcuateboundary. In yet another more detailed embodiment, the firstlongitudinal arm, the primary spring, and the second longitudinal armare fabricated from at least one of a polymer, a composite, concrete, ametal, wood, and a ceramic, the secondary spring is fabricated from atleast one of a polymer, a composite, concrete, a metal, wood, and aceramic. In a further detailed embodiment, the first longitudinal arm,the primary spring, and the second longitudinal arm are fabricated froma polymer, and the secondary spring is fabricated from a metal. In stilla further detailed embodiment, the first longitudinal arm, the primaryspring, and the second longitudinal arm are fabricated from the samepolymer. In a more detailed embodiment, the secondary spring includes aU-shape. In a more detailed embodiment, the secondary spring includes alongitudinal cross section comprising at least one of circular,rectangular, triangular, and oblong. In another more detailedembodiment, the secondary spring comprises a discontinuous loop having afirst closed end and a second open end, the second open end beingpartially defined by a pair of spaced apart legs each having an arcuateprojection.

It is a second aspect of the present invention to provide an occlusionclamp comprising: (a) a first jaw including a first occlusion surface;(b) a second jaw repositionably mounted to the first jaw, the second jawincluding a second occlusion surface; (c) a primary spring removablycoupled to the first jaw and the second jaw to exert a first bias actingon proximal ends of the first and second jaws; and, (d) a secondaryspring removably coupled to the first jaw and the second jaw to exert asecond bias acting on distal ends of the first and second jaws.

In a more detailed embodiment of the second aspect, the second jaw isconfigured to be pivotally and radially repositionably mounted to thefirst jaw. In yet another more detailed embodiment, the occlusion clampfurther includes a pin mounted to the second jaw, wherein the first jawincludes an orifice sized to allow at least partial throughput of thepin and radial movement of the pin within a boundary of the orifice. Ina further detailed embodiment, at least a portion of the pin includes acircular cross-section, and the second jaw includes a cavity configuredto receive a projection of the pin in a friction fit to mount the pintto the second jaw. In still a further detailed embodiment, at least aportion of the pin includes a circular cross-section, and the second jawincludes a projection configured to be received by a cavity of the pinto mount the pin to the second jaw via a friction fit. In a moredetailed embodiment, the first jaw includes a first elongated platformhaving a dominant lengthwise dimension, and the second jaw includes asecond elongated platform having a dominant lengthwise dimension andconfigured to vertically overlap the first elongated platform. In a moredetailed embodiment, the first jaw includes a first hub extending fromthe first elongated platform in the lengthwise dimension, the first hubhaving a widthwise dimension perpendicular to the lengthwise dimensionthat is less than a widthwise dimension of the first elongated platform,the first hub includes a height dimension perpendicular to thelengthwise dimension and the widthwise dimension, the height dimensionof the first hub being greater than a height dimension of the firstelongated platform, the second jaw includes a second hub extending fromthe second elongated platform in the lengthwise dimension, the secondhub having a widthwise dimension perpendicular to the lengthwisedimension that is less than a widthwise dimension of the secondelongated platform, and the second hub includes a height dimensionperpendicular to the lengthwise dimension and the widthwise dimension,the height dimension of the second hub being greater than a heightdimension of the second elongated platform. In another more detailedembodiment, the first jaw includes a first hub extending from the firstelongated platform, the second jaw includes a second hub extending fromthe second elongated platform, and the first hub is configured tohorizontally overlap the second hub. In yet another more detailedembodiment, the first jaw includes a first elongated platform and afirst hub, the second jaw includes a second elongated platform and asecond hub, the first hub includes a cavity sized to house the primaryspring, and the primary spring is concurrently mounted to the first huband at least one of the second hub and the pin. In still another moredetailed embodiment, the primary spring includes a U-shaped portion.

In yet another more detailed embodiment of the second aspect, theprimary spring comprises a discontinuous loop. In yet another moredetailed embodiment, the primary spring comprises a continuous loop. Ina further detailed embodiment, the primary spring is fabricated from atleast one of a polymer, a composite, and a metal. In still a furtherdetailed embodiment, the primary spring is configured to exert a firstbias to retard radial repositioning between the first jaw and the secondjaw, and the secondary spring is configured to exert a second bias toretard pivotal repositioning between the first jaw and the second jaw.In a more detailed embodiment, the secondary spring includes a U-shapedportion. In a more detailed embodiment, the secondary spring comprises adiscontinuous loop. In another more detailed embodiment, the first jawincludes a first trench, the second jaw includes a second trench, andthe secondary spring is configured to be received concurrently with thefirst trench and the second trench when coupled to the first jaw and thesecond jaw. In yet another more detailed embodiment, the first jawincludes a first projection, the second jaw includes a secondprojection, and the secondary spring is configured to concurrentlyreceive the first projection and the second projection when coupled tothe first jaw and the second jaw. In still another more detailedembodiment, the first jaw includes a substantially planar firstocclusion surface, the second jaw includes a substantially planar secondocclusion surface, a lengthwise dimension of the first occlusion surfaceis larger than a widthwise dimension perpendicular to the lengthwisedimension, a lengthwise dimension of the second occlusion surface islarger than a widthwise dimension perpendicular to the lengthwisedimension. In a more detailed embodiment of the third aspect, thesecondary spring is fabricated from at least one of a polymer, acomposite, and a metal.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an elevated perspective view of a first exemplary occlusionclip in accordance with the instant disclosure.

FIG. 2 is a perspective view of the exemplary embodiment of FIG. 1 .

FIG. 3 is a profile view of the exemplary embodiment of FIG. 1 .

FIG. 4 is a cross-sectional view of the exemplary tongs part of theexemplary embodiment of FIG. 1 .

FIG. 5 is an elevated perspective view from a left side of the exemplaryprimary spring of the exemplary embodiment of FIG. 1 .

FIG. 6 is an elevated perspective view from a right side of theexemplary primary spring of the exemplary embodiment of FIG. 1 .

FIG. 7 is an elevated perspective view of an exemplary spring inaccordance with the first and second exemplary embodiments.

FIG. 8 is a profile view of the exemplary spring of FIG. 7 .

FIG. 9 is an elevated perspective view from the front of a secondexemplary occlusion clip in accordance with the instant disclosure.

FIG. 10 is a profile view from the front of the second exemplaryocclusion clip of FIG. 9 .

FIG. 11 is an elevated perspective view from the rear of the secondexemplary occlusion clip of FIG. 9 .

FIG. 12 is an elevated perspective view from the front of a first jaw ofthe second exemplary occlusion clip of FIG. 9 .

FIG. 13 is an elevated perspective view from the rear of the first jawof the second exemplary occlusion clip of FIG. 9 , shown with a firstsecondary spring and pin mounted to the first jaw.

FIG. 14 is an elevated perspective view from the rear of the first jawof the second exemplary occlusion clip of FIG. 9 .

FIG. 15 is a bottom view of the first jaw of the second exemplaryocclusion clip of FIG. 9 .

FIG. 16 is a bottom perspective view from the front of a second jaw ofthe second exemplary occlusion clip of FIG. 9 .

FIG. 17 is an elevated perspective view from the front of the second jawof the second exemplary occlusion clip of FIG. 9 .

FIG. 18 is an elevated perspective view from the left of an alternatefirst jaw that may be used in lieu of the first jaw with the occlusionclip of FIG. 9 , shown with an alternate first secondary spring and pinmounted to the alternate first jaw.

FIG. 19 is a bottom perspective view from the left of the alternatefirst jaw of FIG. 18 .

FIG. 20 is a cross-sectional view of a first alternate exemplary tongsin accordance with the instant disclosure.

FIG. 21 is a cross-sectional view of a second alternate exemplary tongsin accordance with the instant disclosure.

FIG. 22 is a profile view of a first alternate exemplary spring inaccordance with the instant disclosure.

FIG. 23 is a profile view of a second alternate exemplary spring inaccordance with the instant disclosure.

DETAILED DESCRIPTION

The exemplary embodiments of the present disclosure are described andillustrated below to encompass devices, methods, and techniques forfabricating, operation of, and implanting an occlusion clip. Of course,it will be apparent to those of ordinary skill in the art that theembodiments discussed below are exemplary in nature and may bereconfigured without departing from the scope and spirit of the presentdisclosure. However, for clarity and precision, the exemplaryembodiments as discussed below may include optional steps, methods, andfeatures that one of ordinary skill should recognize as not being arequisite to fall within the scope of the present disclosure.Accordingly, it should be understood that the following detaileddescription of embodiments of the present disclosure are exemplary innature and are not intended to constitute limitations upon the presentinvention. It is also to be understood that variations of the exemplaryembodiments contemplated by one of ordinary skill in the art shallconcurrently fall within the scope and spirit of the invention.

Referencing FIGS. 1-8 , a first exemplary occlusion clip 100 includestongs 110 that are repositionable with respect to a secondary spring120. In this exemplary embodiment, the tongs 110 may be fabricated fromvarious materials such as, without limitation, a biologic material, abiologically reabsorbable material, a plastic, a metal, a metal alloy,and carbon fiber. In further exemplary form, the material may beformulated, include additives, or naturally be reabsorbable by amammalian body within a predetermined period of time, such as six monthsor longer.

The secondary spring 120 may be fabricated from various such as, withoutlimitation, a biologic material, a biologically reabsorbable material, aplastic, a metal, a metal alloy, and carbon fiber.

In exemplary form, the tongs 110 include a first longitudinal segment130 that is mounted to a second longitudinal segment 132 by way of aprimary spring 134. The primary spring 134 operates to bias a proximalportion of both the first and second longitudinal segments 130, 132toward one another, while a distal portion of both the first and secondlongitudinal segments are biased toward one another using the secondaryspring 120. In this exemplary embodiment, each longitudinal segment 130,132 is a mirror image of the other and comprises a generally linear armextending from the primary spring 134. But it should also be noted thatthe longitudinal segments need not be mirror images of one another.

A first exterior surface 140 of the longitudinal segments 130, 132 issubstantially convex and includes a semicircular cross-sectionperpendicular to the longitudinal length thereof. This first surfaceseamlessly transitions into a pair of lateral surfaces 142, 144 thatextend substantially parallel to one another and spaced apart from oneanother the width of the segment. Each lateral surface 142, 144terminates at a respective rounded edge 146, 148 that transitions into aconcave interior surface 150. The concave interior surface 150 has asubstantially uniform, semicircular cross-section perpendicular to thelongitudinal length thereof and provides a linear, longitudinal channel152 within which a portion of the secondary spring 120 traverses. Thethree exterior surfaces 140, 142, 144 and the interior surface 150longitudinally converge at a distal end 154 that is substantially planarand perpendicular with respect to the exterior surfaces and interiorsurface, but for a rounded transition 156 linking the surfaces to oneanother.

Opposite the distal ends 154 of the longitudinal segments 130, 132 isthe primary loop spring 134. In this exemplary embodiment, the primaryspring 134 is integrally formed with the longitudinal segments 130, 132and, in this fashion, provides a seamless transition therebetween. Theprimary spring 134 includes a central discontinuous loop 160 having anouter circumferential surface 162 with a substantially constant outerdiameter until reaching a bottleneck 164. This bottleneck 164 connectsthe discontinuous loop 160 to proximal arcuate housing segments 166,168, that themselves are coupled to the longitudinal segments 130, 132.

Referring back to the discontinuous loop 160, lateral and medial ends ofthe circumferential surface 162 are rounded over to transition to a pairof parallel, spaced apart medial and lateral surfaces 170, 172. Aninterior of the primary spring 134 is hollow and includes a throughorifice extending in the medial-lateral direction. This orifice ispartially bound by a pair of parallel, flat walls 176 that are connectedat respective ends to an arcuate wall 178. Opposite the arcuate wall 178is a complementary arcuate wall comprising a first segment 182 spacedapart from a second segment 184 to delineate a slit 186 therebetween. Inexemplary form, the slit 186 extends in the medial-lateral direction aswell as the proximal-distal direction to provide separation between thehousing segments 166, 168.

A proximal end of each housing segment 166, 168 is adjacent a partialopening 190 that extends in the medial-lateral direction and in theanterior-posterior direction (which is perpendicular to themedial-lateral direction and the proximal-distal direction). At theanterior and posterior ends of this opening 190 are a pair of spacedapart walls 194, 196 that delineate an arcuate groove 200 having aconcave, U-shaped profile. A distal end of the arcuate groove 200seamlessly transitions into the longitudinal channel 152. As will bediscussed in more detail hereafter, the arcuate groove 200 andlongitudinal channel 152 are adapted to receive a portion of thesecondary spring 120. Interposing the housing segments 166, 168 and thelongitudinal segments 130, 132 is a transition area 210 that maintainsthe cross-section of the longitudinal channel 152 and also increases ananterior-posterior height to reach the substantially constantanterior-posterior height of the longitudinal segments. In thisexemplary embodiment, the transition area 210 includes an arcuateprofile where the anterior-posterior height gradually increases to matchthat of the longitudinal segment attached thereto. As a result, thetransition area 210 and the housing segments 166, 168 cooperate todefine an internal cavity within which the primary spring 134 ispositioned.

Referring to FIGS. 7 and 8 , an exemplary secondary spring 120 inaccordance with the instant disclosure includes a circular cross-sectionthat is generally perpendicular to the longitudinal length thereof,which is the dominant dimension of the secondary spring. Whilecomprising an integrated structure, the secondary spring 120 can becharacterized as including three sections, two of which are repeated. Afirst section 220 is generally U-shaped and includes a substantiallyconstant radial arc to resemble a semi-circle. This first section 220 isintegrally formed with a pair of second sections 222 at the distal endsof the first section and a proximal end of each second section. Each ofthe second sections 222 includes a substantially linear length thatextends perpendicularly away from the first section and in parallel toone another and may be biased toward one another to achieve the desiredcompression force. A distal end of each second section 222 is mounted toa third section 224 that includes a sinusoidal shape. This sinusoidalshape is typified by a convex exterior surface 228 that operates todecrease an anterior-posterior gap 230 that is present along alongitudinal interior of the secondary spring. More specifically, thegap 230 between the second sections 222 is greater than the gap betweenthe third sections 224. As will be discussed in more detail hereafter,the third sections 224 are partially received within a depression formedinto the longitudinal segments 130, 132 along a length of thelongitudinal channel 152.

Referencing FIGS. 1-3 , assembly and utilization of the exemplaryocclusion clip 100 includes repositioning the tongs 110 so that tissueto be occluded is positioned between the exterior surfaces 140 of thelongitudinal segments 130, 132. In exemplary form, the tissue to beoccluded may be a human left atrial appendage (not shown).

By way of example, the tongs 110 is positioned so that the longitudinalsegments 130, 132 are parallel and compressed against one another toallow the tongs to pass through a trocar. After passing through thetrocar and into a mammalian chest cavity, a spacing between distal endsof the longitudinal segments 130, 132 is increased so that the spacingbetween the segments is large enough to accommodate a left atrialappendage of a heart.

After the tissue in question, in this case the left atrial appendage, ispositioned between the longitudinal segments 130, 132, the longitudinalsegments are moved closer to one another. This may be accomplished bymanually compressing the longitudinal segments 130, 132 toward oneanother or by using the secondary spring 120 to move the longitudinalsegments toward one another. For purposes of discussion, it will bepresumed that that secondary spring 120 is utilized to compress thelongitudinal segments 130, 132 toward one another.

In order to use the secondary spring 120 to compress the longitudinalsegments toward one another, the secondary spring is inserted throughthe trocar and into alignment with the tongs, presuming this alignmentis not already completed. More specifically, the third sections 224 ofthe secondary spring 120 are aligned with the proximal end of the tongs110 so that each of the third sections is at least partially receivedwithin a corresponding arcuate groove 200. At this time, the secondaryspring 120 is repositioned in the distal direction with respect to thetongs 110 so that the convex exterior surface 228 contacts the surfacedelineating the arcuate groove 200. Continued movement of the secondaryspring 120 toward the distal end of the tongs 110 causes the thirdsections 224 to increase the gap 230 therebetween to accommodate thetongs. The resilient nature of the secondary spring 120, resulting froman increase in the gap 230, exerts a bias force that causes thelongitudinal segments 130, 132 to be compressed toward one another. Evenfurther movement of the secondary spring 120 toward the distal end ofthe tongs 110 causes the spacing between the longitudinal segments 130,132 to decrease and compress the segments against the tissue inquestion, in this case the left atrial appendage. The further along thesecondary spring moves distally with respect to the tongs 110, thegreater the moment that is exerted against the longitudinal members 130,132 because the moment necessary to move the second sections 222 apartincreases as one moves closer to the first section 220. Eventually,movement of the secondary spring 120 toward the distal end of the tongs110 reaches a point where both third sections 224 are received withinsecondary depressions 250 formed deeper into the longitudinal segments130, 132 as part of the longitudinal channels 152.

It should be noted that while the exemplary embodiment includes a singlesecondary depression 250 for each of the longitudinal members 130, 132,it is also within the scope of the disclosure to provide multiplesecondary depressions 250 longitudinally distributed along thelongitudinal members in order to accommodate ranges of force balancing,such as the alternate exemplary tongs 110′ depicted in FIG. 20 .Likewise, while the exemplary secondary spring 120 has been shown toinclude a pair of third sections 224, one adapted to engage eachlongitudinal member 130, 132, it is also within the scope of thedisclosure for a second alternate secondary spring 120″, 314″, such asdepicted in FIG. 23 , to include multiple projections 241 in seriesand/or spaced apart from one another to engage one or more of thesecondary depressions 250 of each longitudinal member of the alternateexemplary tongs 110′. Conversely, it is also within the scope of thedisclosure to provide multiple secondary depressions 231 longitudinallydistributed along the longitudinal members, such as shown in FIG. 22 ,in order to accommodate ranges of force balancing, such as the secondexemplary tongs 110″ depicted in FIG. 21 that include a plurality ofsecondary projections 251 distributed along each longitudinal member.

When the secondary depressions 250 receive the third sections 224 of thesecondary spring 120, the secondary spring 120 is relatively locked intoa longitudinal friction fit with respect to the tongs 110. Likewise,when the secondary depressions 250 receive the third sections 224 of thesecondary spring 120, a bias exerted upon the longitudinal segments 130,132 is approximately equal along the longitudinal length thereof. Thislongitudinal bias is operate to occlude the tissue clamped between thelongitudinal segments 130, 132 and is the cooperative product of thebias of the secondary spring 120 and the bias of the primary spring 134.More specifically, the secondary spring 120 may be selected based uponthe bias it exerts to match that of the primary spring 134. Conversely,the primary spring 134 may be designed to include a bias that matchesthat of a predetermined secondary spring 120.

Disassembly of the exemplary occlusion clip 100 includes repositioningthe secondary spring 120 proximally with respect to the tongs 110 sothat the third sections 224 become displaced from the depressions 250.Eventually, continued proximal movement of the secondary spring 120 withrespect to the tongs 110 results in the third sections 224 passingbeyond the proximal most portion of the tongs, resulting in completedisengagement between the tongs and secondary spring.

While the foregoing exemplary secondary spring 120 has been shown anddescribed as having a uniform, circular cross-section along thelongitudinal length thereof, it is also within the scope of thisdisclosure to provide differing cross-sections. By way of example, thecross-section of the secondary spring 120 may take on a rectangularshape having a dominant dimension that makes distortion in a first planemore difficult that distortion in a second plane, perpendicular to thefirst plane, typified by a subordinate dimension. Moreover, thecross-section of the secondary spring 120 may change along itslongitudinal length. By way of example, a circular cross-section may beexhibited by a portion of the secondary spring, followed by anon-circular cross section (e.g., an oblong shape, rectangular shape, orotherwise). In other words, the cross-section along the length of thesecondary spring may have a portion that is configured to retard motionor more readily allow motion in one or more directions, followed by orproceeded by a portion having a different cross-section that isconfigured to retard motion or more readily allow motion in one or moreof the same or different directions. By way of further example, theU-shaped proximal first section 220 of the secondary spring 120 may havea circular cross-section, while the second sections 222 may have arectangular profile with a dominant dimension in the lateral directionto allow greater deflection up or down rather than side to side. Thesedifferent cross-sections may be useful to balance forces applied by thelongitudinal segments 130, 132.

Referring to FIGS. 7-17 , a second exemplary occlusion clip 300 includesa first jaw 310 repositionably mounted to a second jaw 312 and adaptedto be biased toward one another using a secondary spring 314. In thisexemplary embodiment, the jaws 310, 312 are fabricated from a resilientor partially resilient material such as, without limitation, a biologicmaterial, a biologically reabsorbable material, a plastic, a metal, ametal alloy, and carbon fiber. In further exemplary form, the materialmay be formulated, include additives, or naturally be reabsorbable by amammalian body within a predetermined period of time, such as six monthsor longer.

The spring 314 is also fabricated from a resilient material. Exemplarymaterials used to fabricate the spring 314 include, without limitation,a biologic material, a biologically reabsorbable material, a plastic, ametal, a metal alloy, and carbon fiber.

Referring to FIGS. 11-13 , the first jaw 310 includes an elongatedplatform 320 that extends from a hub 322. The elongated platform 320comprises an inclined occlusion surface 326 that is substantially planarbut causes the height of the platform to gradually increase from adistal tip 328 to a proximal ending 334. Opposite the inclined surfaceis a bottom surface 330 having formed therein a longitudinal trench 332having a substantially rectangular cross-section that extends partiallybeyond the proximal ending 334. It should be noted that the longitudinaltrench 332 may have a cross-section other than rectangular including,without limitation, oblong and semicircular. The distal tip 328interposes the inclined surface 326 and the bottom surface 330, alongwith a pair of spaced apart, planar lateral surfaces 340, 342. Theplanar lateral surfaces 340, 342 are each generally perpendicular to theinclined surface 326 and the bottom surface 330.

The hub 322 is located proximate the elongated platform 320 and islaterally inset with respect to one of the lateral surfaces 342, butflush with respect to the other lateral surface 340. A distal portion350 of the hub 322 includes an arcuate profile from distal to proximaland rounds over at a proximal portion 352. The distal and proximalportions 350, 352 include a peripheral flange 354 having a pair ofparallel, linear segments 356, 358 extending into the interior of thehub 322. Just above the first linear segment 356 is an oblong throughopening 364 delineated by an oblong interior wall 366. Morespecifically, the opening 364 extends through a wall having a pair ofparallel, lateral surfaces 370, 372. In particular, the first lateralsurface 370 is co-planar with the lateral surface 340 of the elongatedplatform 320.

A primary spring 378 is received within the interior of the hub 322 andconfigured to provide bias for a proximal end of the exemplary occlusionclip 300. More specifically, a cylindrical pin 380 extends through theoblong opening 364 and into the interior of the hub 322, where a smallerdiameter portion 382 of the cylindrical pin is adapted to be receivedwithin a through hole of the second jaw 312. A lower portion of thecylindrical pin 380 is bounded by the first linear segment 356, while anupper portion of the cylindrical pin is bounded by the primary spring378. In this manner, the cylindrical pin 380 is able to move verticallywithin the oblong opening 364, but to do so the bias of the primaryspring 378 must be overcome. In this exemplary embodiment, the primaryspring 378 comprises a simple U-shaped configuration and where one ofthe ends of the spring is received between the linear segments 356, 358,while the arcuate portion of the secondary spring abuts the peripheralflange 354. In this manner, the primary spring 378 is relativelystationary, but may be deformed to allow the cylindrical pin 380 tovertically travel within the oblong opening 364, thereby allowing aproximal spacing between the jaws 310, 312 to be changed.

Referring to FIGS. 16 and 17 , the second jaw 312 includes an elongatedplatform 420 that extends from a solid hub 422. The elongated platform420 comprises an inclined occlusion surface 426 that is substantiallyplanar but causes the height of the platform to gradually increase froma distal tip 428 to a proximal ending 434. Opposite the inclined surfaceis a bottom surface 430 having formed therein a longitudinal trench 432having a substantially rectangular cross-section that extends partiallybeyond the proximal ending 434. It should be noted that the longitudinaltrench 432 may have a cross-section other than rectangular including,without limitation, oblong and semicircular. The distal tip 428interposes the inclined surface 426 and the bottom surface 430, alongwith a pair of spaced apart, planar lateral surfaces 440, 442. Theplanar lateral surfaces 440, 442 are each generally perpendicular to theinclined surface 426 and the bottom surface 430.

The solid hub 422 comprises a pair parallel, spaced apart lateralsurfaces 450, 452 that are bounded by an arcuate circumferential surface454. In this exemplary embodiment, the interior lateral surface 450includes an orifice 460 (see FIG. 11 ) that receives the smallerdiameter portion 382 of the cylindrical pin 380 via a friction fit,thereby joining the jaws to one another. In this exemplary embodiment,the cylindrical pin 380 includes an oversized head 384 that provides aboundary for the first jaw 310 in order to allow the jaws 310, 312 tomove with respect to one another, but inhibit lateral disengagementbetween the jaws where the jaws might otherwise come apart.

In this exemplary embodiment, the secondary spring 314 includesgenerally the same structure and shape as the secondary spring 120 ofthe first exemplary embodiment, which is shown in FIGS. 7 and 8 .Accordingly, description of the spring 314 has been omitted in thisexemplary embodiment in furtherance of brevity.

Referring back to FIGS. 9-17 , assembly and utilization of the exemplaryocclusion clip 300 includes repositioning the jaws 310, 312 so thattissue to be occluded is positioned between the inclined surfaces 326 ofthe elongated platforms 320. In exemplary form, the tissue to beoccluded may be a human left atrial appendage (not shown).

By way of example, the jaws 310, 312 are positioned so that the inclinedsurfaces 326 of the elongated platforms 320 are parallel and compressedagainst one another to allow the jaws to pass through a trocar. Afterpassing through the trocar and into a mammalian chest cavity, a spacingbetween the inclined surfaces 326 of the elongated platforms 320 isincreased by overcoming the bias of the primary spring 378 in order tovertically reposition the second jaw 312 with respect to the first jaw310 so that the pin 380 is against an uppermost portion of the oblonginterior wall 366 so that the spacing therebetween is large enough toaccommodate a left atrial appendage of a heart.

After the tissue in question, in this case the left atrial appendage, ispositioned between the inclined surfaces 326 of the elongated platforms320, the elongated platforms are allowed to move closer to one another,in part by discontinuing to overcome the bias of the primary spring 378.In addition, additional bias is applied to the jaws 310, 312 by mountingthe spring 314 to the jaws so the elongated platforms 320, 420 arecompressed toward one another.

In order to use the spring 314 to compress the inclined surfaces 326,426 of the elongated platforms 320, 420 toward one another, the springis first inserted through the trocar and into alignment with the jaws310, 312, presuming the spring is not already in alignment with theelongated platforms. More specifically, the third sections 224 of thespring 314 are aligned with the longitudinal trenches 332, 432 so thatthe third sections contact the hubs 322, 422 of both jaws 310, 312.Further movement of the spring 314 in the distal direction with respectto the jaws 310, 312 causes the third sections 224 to increase the gap230 therebetween to accommodate the jaws so that the third sectionsbecome seated within the longitudinal trenches 332, 432. The resilientnature of the spring 314, resulting from an increase in the gap 230,exerts a bias force that causes the inclined surfaces 326, 426 of theelongated platforms 320, 420 to be compressed toward one another.Further movement of the spring 314 toward the distal ends 328, 428 ofthe elongated platforms 320, 420 causes the spacing between the inclinedsurfaces 326, 426 to decrease and compress the surfaces against thetissue in question, in this case the left atrial appendage.

The further along the spring 314 moves distally with respect to the jaws310, 312, the greater the moment that is exerted against the inclinedsurfaces 326, 426 of the elongated platforms 320, 420 because the momentnecessary to move the surfaces apart increases as one moves closer tothe first section 220. Eventually, movement of the spring 314 toward thedistal end 328, 428 of the jaws 310, 312 reaches a point where continueddistal movement of the spring is no longer possible.

When the spring 314 reaches the point where further distal movement isno longer possible, the spring is locked into a longitudinal frictionfit with respect to the jaws 310, 312. Likewise, when the spring 314reaches its distal most position, a moment exerted upon the jaws 310,312 is approximately equal along the moment exerted upon a proximalportion of the jaws via the primary spring 378. Accordingly, compressionof the jaws 310, 312 is operative to occlude the tissue clamped betweenthe generally parallel, inclined surfaces 326, 426 of the elongatedplatforms 320, 420.

In exemplary form, the jaws 310, 312 may be fabricated from anybiologically compatible material including, without limitation,ceramics, polymers, metals, alloys of the foregoing, and composites.Likewise, the springs 314, 378 may be fabricated from any resilientmaterial including, without limitation, polymers, metals, and alloy ofthe foregoing.

In a preferred embodiment, the longitudinal trenches 332, 432 mayinclude a series of depressions that are longitudinally spaced apartfrom one another and adapted to receive the convex exterior surface 228of the third spring section 224. In exemplary form, the locations of thedepressions may be chosen to balance the moments between the spring 314and the primary spring 378.

Disassembly of the exemplary occlusion clip 300 includes repositioningthe spring 314 proximally with respect to the jaws 310, 312. Eventually,continued proximal movement of the spring 314 with respect to the jaws310, 312 results in the third sections 224 passing beyond the proximalmost portion of the jaws, resulting in complete disengagement betweenthe jaws and spring.

Referring to FIGS. 18 and 19 , an alternate exemplary first jaw 500 thatmay be used in place of the first jaw 310 as part of the secondexemplary occlusion clip 300. In this alternate exemplary first jaw 500,the hub 502 is different from the hub 322 of the first jaw 310. Inparticular, the revised hub 502 includes a peripheral flange 504 thatcooperates with a lateral interior wall 506 to define an interior cavity508. Extending through the lateral interior wall 506 is an oblongthrough opening 512 configured to receive a cylindrical pin 380. In thismanner, the shape of the through opening 512 allows vertical travel ofthe cylindrical pin 380 with respect to the first jaw 500.

Proximate the bottom of the oblong opening 512 and extending from theinterior wall 506 is a platform 516. This platform 516 and thecylindrical pin 380 are concurrently circumscribed by an elastic band520 that operates to exert a bias on the proximal aspects of the jaws500, 312 when coupled to one another. By way of example, the resilientband 520 may be fabricated from any elastic material. In particular, theelastic band 520 resists vertical movement of the cylindrical pin 380away from the platform. Vertical motion between the cylindrical pin 380and the platform 516 causes the vertical spacing to change between thejaws 500, 312 at the proximal ends of the jaws. More specifically, arelatively larger vertical spacing between the cylindrical pin 380 andthe platform 516 corresponds to a larger vertical spacing betweenproximal portions of the jaws 500, 312, whereas a relatively smallervertical spacing between the cylindrical pin and the platformcorresponds to a smaller vertical spacing between proximal portions ofthe jaws. Accordingly, this jaw 500 provides an alternate configurationfor using an elastic band 520, as opposed to using the primary spring378 and the first jaw 310, in combination with the second jaw 312 toform an alternate exemplary occlusion clip.

It is also within the scope of the invention for the exemplary occlusionclips to be shrouded in a tissue ingrowth material. For example, theexemplary occlusion clips may be encased in a C-shaped, loop sleeve thatis cylindrical and closed at opposing ends in order to accommodateopening and closing of the exemplary clips (i.e., separation or spacingbetween the open ends sufficient to position tissue between portions ofthe clips). Those skilled in the art are familiar with tissue ingrowthmaterials such as porous fabrics, including Gore Dualmesh (availablefrom W.L. Gore & Associates, www.gore.com) that may be used as to shroudthe foregoing exemplary embodiments.

Following from the foregoing description, it should be apparent to thoseof ordinary skill in the art that, while the methods and apparatusesherein described constitute exemplary embodiments of the presentinvention, it is to be understood that the inventions described hereinare not limited to the above precise embodiments and that changes may bemade without departing from the scope of the invention as defined by thefollowing claims. Likewise, it is to be understood that it is notnecessary to meet any or all of the identified advantages or objects ofthe invention disclosed herein in order to fall within the scope of theclaims, since inherent and/or unforeseen advantages of the presentinvention may exist even though they may not have been explicitlydiscussed herein.

1-21. (canceled)
 22. A left atrial appendage (LAA) occlusion clip, comprising: a first arm and a second arm separate from one another and each comprising an LAA tissue-contacting surface, a proximal end, and a distal end opposite the proximal end, wherein an end of each of the first and second arms is open, wherein the first arm and the second arm are disposed to face the LAA tissue-contacting surfaces towards one another such that the proximal end of the first arm and the proximal end of the second arm together define a proximal clip end, wherein the distal end of the first arm and the distal end of the second arm define an open clip end opposite the proximal clip end; a first spring connecting the first arm to the second arm, crossing over from the first arm to the second arm adjacent to the proximal clip end; and a second spring separate from the first spring, the second spring connecting the first arm to the second arm and disposed on an exterior surface of the first and second arms, crossing over from the first arm to the second arm adjacent to the proximal clip end.
 23. The LAA occlusion clip of claim 22, wherein the first spring is configured to permit movement of the first and second arms at least towards and away from one another, and wherein the second spring is configured to permit movement of the first and second arms at least towards and away from one another.
 24. The LAA occlusion clip of claim 22, wherein the second spring connects the first arm to the second arm such that distortion of the first and second arms is contained within a first plane.
 25. The LAA occlusion clip of claim 22, wherein the second spring is connected to an intermediate position of the first arm between the distal end and the proximal end of the first arm and an intermediate position of the second arm between the distal end and the proximal end of the second arm.
 26. The LAA occlusion clip of claim 22, wherein the first and second arms and the first and second springs together form the occlusion clip, wherein the occlusion clip is configured to be compressed to allow the occlusion clip to pass through a trocar and into a mammalian chest cavity.
 27. The LAA occlusion clip of claim 22, wherein the first and second arms each have a dominant lengthwise dimension, wherein the second spring has two linear segments each having a longitudinal dimension less than the dominant lengthwise dimension.
 28. The LAA occlusion clip of claim 22, wherein the second spring comprises at least one of a rectangular, circular, triangular, or oblong cross-section.
 29. The LAA occlusion clip of claim 22, wherein the first spring exerts a first bias to inhibit radial repositioning between the first and second arms and the second springs exerts a second bias to inhibit pivotal repositioning between the first and second arms.
 30. The LAA occlusion clip of claim 22, wherein the first and second arms are disposed to face the LAA tissue-contacting surfaces towards one another such that the proximal ends of the first and second arms are adjacent and the distal ends of the first and second arms are adjacent.
 31. The LAA occlusion clip of claim 22, wherein each of the first and second springs is U-shaped.
 32. The LAA occlusion clip of claim 22, wherein the first and second arms each comprise a channel on a side of the respective arm.
 33. The LAA occlusion clip of claim 32, wherein the side of each of the first and second arms comprising the channel is different than a side of each of the first and second arms comprising the LAA tissue-contacting surface.
 34. The LAA occlusion clip of claim 32, wherein the channel of each of the first and second arms is configured to receive a portion of the second spring.
 35. The LAA occlusion clip of claim 22, wherein the first spring does not interpose the LAA tissue-contacting surfaces.
 36. The LAA occlusion clip of claim 22, wherein the second spring does not interpose the LAA tissue-contacting surfaces.
 37. The LAA occlusion clip of claim 22, wherein the curved portion of the first spring is positioned adjacent the proximal portions of the first and second arms. 